Objective:To explore the relationship and underlying mechanisms between servant leadership and satisfaction of medical staff in tertiary hospitals, and to provide references for improving satisfaction of medical personnel.Methods:From January to June 2023, a questionnaire survey was conducted among on-duty medical staff at a tertiary hospital in Guangzhou using a simple random sampling method. Data corresponding to four key variables: servant leadership, hospital management level, affective commitment, and satisfaction of medical staff were collected. SPSS 25.0 software was used to perform independent samples t-tests and one-way analysis of variance (ANOVA) to examine group differences, and Pearson correlation analysis was conducted to explore the relationships among multiple variables. Amos 24.0 software was employed to construct a structural equation model to conduct confirmatory factor analysis of the four key variables, analyze potential mediating effects, and use multi-group analysis to examine differences in path parameters and structure among groups. Results:A total of 632 valid questionnaires were obtained. The satisfaction score of medical staff was (4.50±0.66)(maximum score was 5 points). Age, years of work experience, and job category had statistically significant effects on satisfaction of medical staff ( F = 5.799, 6.483, 7.671; P = 0.001). All four key variables were significantly positively correlated ( P<0.001). Servant leadership, hospital management level, and affective commitment all had direct positive effects on satisfaction of medical staff, with path coefficients of 0.207, 0.386, and 0.345, respectively ( P <0.05, critical ratio>1.96). Hospital management level and affective commitment each had independent partial mediating effects between servant leadership and satisfaction of medical staff (path coefficients of 0.353 and 0.067, respectively; P = 0.007, 0.018). They also jointly exerted a chain mediating effect (path coefficient of 0.243, P = 0.013). Differences in path effects among different job categories (clinical doctors, nurses, and administrative support staff) were statistically significant ( χ2 = 43.344, df = 24, P = 0.009). Conclusions:The servant leadership in tertiary hospitals can directly influence the satisfaction of medical staff, as well as indirectly influence it through emotional commitment and hospital management level. Moreover, the mechanisms of influence vary among medical staff of different professional categories. Tertiary hospitals should introduce and promote servant leadership styles, enhance the servant leadership behaviors of management personnel, and strengthen the synergistic effects of servant leadership, hospital management level, and affective commitment. Differential adjustment mechanisms should be implemented for different job categories.

Objective:To explore the relationship and underlying mechanisms between servant leadership and satisfaction of medical staff in tertiary hospitals, and to provide references for improving satisfaction of medical personnel.Methods:From January to June 2023, a questionnaire survey was conducted among on-duty medical staff at a tertiary hospital in Guangzhou using a simple random sampling method. Data corresponding to four key variables: servant leadership, hospital management level, affective commitment, and satisfaction of medical staff were collected. SPSS 25.0 software was used to perform independent samples t-tests and one-way analysis of variance (ANOVA) to examine group differences, and Pearson correlation analysis was conducted to explore the relationships among multiple variables. Amos 24.0 software was employed to construct a structural equation model to conduct confirmatory factor analysis of the four key variables, analyze potential mediating effects, and use multi-group analysis to examine differences in path parameters and structure among groups. Results:A total of 632 valid questionnaires were obtained. The satisfaction score of medical staff was (4.50±0.66)(maximum score was 5 points). Age, years of work experience, and job category had statistically significant effects on satisfaction of medical staff ( F = 5.799, 6.483, 7.671; P = 0.001). All four key variables were significantly positively correlated ( P<0.001). Servant leadership, hospital management level, and affective commitment all had direct positive effects on satisfaction of medical staff, with path coefficients of 0.207, 0.386, and 0.345, respectively ( P <0.05, critical ratio>1.96). Hospital management level and affective commitment each had independent partial mediating effects between servant leadership and satisfaction of medical staff (path coefficients of 0.353 and 0.067, respectively; P = 0.007, 0.018). They also jointly exerted a chain mediating effect (path coefficient of 0.243, P = 0.013). Differences in path effects among different job categories (clinical doctors, nurses, and administrative support staff) were statistically significant ( χ2 = 43.344, df = 24, P = 0.009). Conclusions:The servant leadership in tertiary hospitals can directly influence the satisfaction of medical staff, as well as indirectly influence it through emotional commitment and hospital management level. Moreover, the mechanisms of influence vary among medical staff of different professional categories. Tertiary hospitals should introduce and promote servant leadership styles, enhance the servant leadership behaviors of management personnel, and strengthen the synergistic effects of servant leadership, hospital management level, and affective commitment. Differential adjustment mechanisms should be implemented for different job categories.

OBJECTIVE To investigate the effects of sacubitril/valsartan on renal function in patients with primary hypertension. METHODS A retrospective study was conducted among patients with primary hypertension who were admitted to PLA Strategic Support Force Characteristic Medical Center from January 2018 to June 2023. Based on their medication， they were divided into two groups： sacubitril/valsartan group and valsartan group. Propensity score matching was used to match baseline data between the two groups. Patients were treated with antihypertensive drugs based on improving their lifestyle. Sacubitril/valsartan group additionally received oral administration of 200 mg Sacubitril/valsartan tablets once daily， while valsartan group additionally received oral administration of 80 mg Valsartan capsules once daily. The increase amplitude of serum creatinine from baseline， the proportion of patients with elevated serum creatinine ＞30%-50% or ＞50%， and the proportion of patients with hyperkalemia （serum potassium ≥5.5 mmol/L） were compared between two groups at 2 months and 6 months after treatment. The trends of changes in serum creatinine， serum potassium and estimated glomerular filtration rate （eGFR） were compared between the two groups before treatment （at baseline）， 2 months and 6 months after treatment. RESULTS After propensity score matching， there were 62 patients in sacubitril/valsartan group and 61 patients in valsartan group； there were no significant differences in baseline characteristics between the two groups before treatment （P＞0.05）， indicating comparability. After 6 months of treatment， the increase of serum creatinine in the sacubitril/valsartan group was significantly lower than that in the valsartan group （P＝0.003）； the proportion of patients with elevated serum creatinine ＞30%-50% in the sacubitril/valsartan group was significantly lower than that in the valsartan group （P＝0.045）. None of the patients experienced hyperkalemia events after 2 months and 6 months of treatment. Repeated measures analysis of variance showed significantly statistical differences in serum creatinine and eGFR between the two groups within 6 months of treatment （P＜0.001）. Patients taking valsartan experienced a continuous increase in serum creatinine levels and a decrease in eGFR， while patients taking sacubitril/valsartan showed a first increase and then a decrease in serum creatinine levels， and a first decrease and then an increase in eGFR with a prolonged duration of medication. CONCLUSIONS Sacubitril/valsartan can delay or even reverse the decline in renal function levels， and limit the deterioration of renal function in patients with primary hypertension， without increasing the risk of hyperkalemia.

A 61-year-old male patient with coronary heart disease was treated with dual antiplatelet therapy, lipid-lowering therapy (atorvastatin) and other symptomatic drugs after coronary interventions. Because the patient was at ultra-high-risk of cardiovascular events, had multiple in-stent restenosis, and had uncontrolled blood lipids, subcutaneous injection of evolocumab 140 mg was added once every 2 weeks. The platelet count (PLT) of the patient was within the reference range before evolocumab application. After 2 injections of evolocumab, he developed bloody sputum, blood blisters on the lips and scattered bleeding points around the body, with PLT 19×10 9/L. The dual antiplatelet therapy and evolocumab were suspended, but the bleeding was aggravated. According to the results of bone marrow puncture and biopsy, the patient was diagnosed with idiopathic thrombocytopenic purpura. Glucocorticoid, human immunoglobulin, recombinant human thrombopoietin and platelet transfusion were given but not effective. Subsequently, herombopag was added and PLT gradually increased. After 25 days, the PLT was 109×10 9/L.

A 61-year-old male patient with coronary heart disease was treated with dual antiplatelet therapy, lipid-lowering therapy (atorvastatin) and other symptomatic drugs after coronary interventions. Because the patient was at ultra-high-risk of cardiovascular events, had multiple in-stent restenosis, and had uncontrolled blood lipids, subcutaneous injection of evolocumab 140 mg was added once every 2 weeks. The platelet count (PLT) of the patient was within the reference range before evolocumab application. After 2 injections of evolocumab, he developed bloody sputum, blood blisters on the lips and scattered bleeding points around the body, with PLT 19×10 9/L. The dual antiplatelet therapy and evolocumab were suspended, but the bleeding was aggravated. According to the results of bone marrow puncture and biopsy, the patient was diagnosed with idiopathic thrombocytopenic purpura. Glucocorticoid, human immunoglobulin, recombinant human thrombopoietin and platelet transfusion were given but not effective. Subsequently, herombopag was added and PLT gradually increased. After 25 days, the PLT was 109×10 9/L.

Objective:To investigate the epidemiological characteristics, diagnosis, treat-ment and prognosis of gallbladder cancer in China from 2010 to 2017.Methods:The single disease retrospective registration cohort study was conducted. Based on the concept of the real world study, the clinicopathological data, from multicenter retrospective clinical data database of gallbladder cancer of Chinese Research Group of Gallbladder Cancer (CRGGC), of 6 159 patients with gallbladder cancer who were admitted to 42 hospitals from January 2010 to December 2017 were collected. Observation indicators: (1) case resources; (2) age and sex distribution; (3) diagnosis; (4) surgical treatment and prognosis; (5) multimodality therapy and prognosis. The follow-up data of the 42 hospitals were collected and analyzed by the CRGGC. The main outcome indicator was the overall survival time from date of operation for surgical patients or date of diagnosis for non-surgical patients to the end of outcome event or the last follow-up. Measurement data with normal distribu-tion were represented as Mean±SD, and comparison between groups was conducted using the t test. Measurement data with skewed distribution were represented as M( Q1, Q3) or M(range), and com-parison between groups was conducted using the U test. Count data were described as absolute numbers or percentages, and comparison between groups was conducted using the chi-square test. Univariate analysis was performed using the Logistic forced regression model, and variables with P<0.1 in the univariate analysis were included for multivariate analysis. Multivariate analysis was performed using the Logistic stepwise regression model. The life table method was used to calculate survival rates and the Kaplan-Meier method was used to draw survival curves. Log-rank test was used for survival analysis. Results:(1) Case resources: of the 42 hospitals, there were 35 class A of tertiary hospitals and 7 class B of tertiary hospitals, 16 hospitals with high admission of gallbladder cancer and 26 hospitals with low admission of gallbladder cancer, respectively. Geographical distribution of the 42 hospitals: there were 9 hospitals in central China, 5 hospitals in northeast China, 22 hospitals in eastern China and 6 hospitals in western China. Geographical distribution of the 6 159 patients: there were 2 154 cases(34.973%) from central China, 705 cases(11.447%) from northeast China, 1 969 cases(31.969%) from eastern China and 1 331 cases(21.611%) from western China. The total average number of cases undergoing diagnosis and treatment in hospitals of the 6 159 patients was 18.3±4.5 per year, in which the average number of cases undergoing diagnosis and treatment in hospitals of 4 974 patients(80.760%) from hospitals with high admission of gallbladder cancer was 38.8±8.9 per year and the average number of cases undergoing diagnosis and treatment in hospitals of 1 185 patients(19.240%) from hospitals with low admission of gallbladder cancer was 5.7±1.9 per year. (2) Age and sex distribution: the age of 6 159 patients diagnosed as gallbladder cancer was 64(56,71) years, in which the age of 2 247 male patients(36.483%) diagnosed as gallbladder cancer was 64(58,71)years and the age of 3 912 female patients(63.517%) diagnosed as gallbladder cancer was 63(55,71)years. The sex ratio of female to male was 1.74:1. Of 6 159 patients, 3 886 cases(63.095%) were diagnosed as gallbladder cancer at 56 to 75 years old. There was a significant difference on age at diagnosis between male and female patients ( Z=-3.99, P<0.001). (3) Diagnosis: of 6 159 patients, 2 503 cases(40.640%) were initially diagnosed as gallbladder cancer and 3 656 cases(59.360%) were initially diagnosed as non-gallbladder cancer. There were 2 110 patients(34.259%) not undergoing surgical treatment, of which 200 cases(9.479%) were initially diagnosed as gallbladder cancer and 1 910 cases(90.521%) were initially diagnosed as non-gallbladder cancer. There were 4 049 patients(65.741%) undergoing surgical treatment, of which 2 303 cases(56.878%) were initially diagnosed as gallbladder cancer and 1 746 cases(43.122%) were initial diagnosed as non-gallbladder cancer. Of the 1 746 patients who were initially diagnosed as non-gallbladder cancer, there were 774 cases(19.116%) diagnosed as gallbladder cancer during operation and 972 cases(24.006%) diagnosed as gallbladder cancer after operation. Of 6 159 patients, there were 2 521 cases(40.932%), 2 335 cases(37.912%) and 1 114 cases(18.087%) undergoing ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) examination before initial diagnosis, respec-tively, and there were 3 259 cases(52.914%), 3 172 cases(51.502%) and 4 016 cases(65.205%) undergoing serum carcinoembryonic antigen, CA19-9 or CA125 examination before initially diagnosis, respectively. One patient may underwent multiple examinations. Results of univariate analysis showed that geographical distribution of hospitals (eastern China or western China), age ≥72 years, gallbladder cancer annual admission of hospitals, whether undergoing ultrasound, CT, MRI, serum carcinoembryonic antigen, CA19-9 or CA125 examination before initially diagnosis were related factors influencing initial diagnosis of gallbladder cancer patients ( odds ratio=1.45, 1.98, 0.69, 0.68, 2.43, 0.41, 1.63, 0.41, 0.39, 0.42, 95% confidence interval as 1.21-1.74, 1.64-2.40, 0.59-0.80, 0.60-0.78, 2.19-2.70, 0.37-0.45, 1.43-1.86, 0.37-0.45, 0.35-0.43, 0.38-0.47, P<0.05). Results of multivariate analysis showed that geographical distribution of hospitals (eastern China or western China), sex, age ≥72 years, gallbladder cancer annual admission of hospitals and cases undergoing ultrasound, CT, serum CA19-9 examination before initially diagnosis were indepen-dent influencing factors influencing initial diagnosis of gallbladder cancer patients ( odds ratio=1.36, 1.42, 0.89, 0.67, 1.85, 1.56, 1.57, 0.39, 95% confidence interval as 1.13-1.64, 1.16-1.73, 0.79-0.99, 0.57-0.78, 1.60-2.14, 1.38-1.77, 1.38-1.79, 0.35-0.43, P<0.05). (4) Surgical treatment and prognosis. Of the 4 049 patients undergoing surgical treatment, there were 2 447 cases(60.435%) with complete pathological staging data and follow-up data. Cases with pathological staging as stage 0, stage Ⅰ, stage Ⅱ, stage Ⅲa, stage Ⅲb, stage Ⅳa and stage Ⅳb were 85(3.474%), 201(8.214%), 71(2.902%), 890(36.371%), 382(15.611%), 33(1.348%) and 785(32.080%), respectively. The median follow-up time and median postoperative overall survival time of the 2 447 cases were 55.75 months (95% confidence interval as 52.78-58.35) and 23.46 months (95% confidence interval as 21.23-25.71), respectively. There was a significant difference in the overall survival between cases with pathological staging as stage 0, stage Ⅰ, stage Ⅱ, stage Ⅲa, stage Ⅲb, stage Ⅳa and stage Ⅳb ( χ2=512.47, P<0.001). Of the 4 049 patients undergoing surgical treatment, there were 2 988 cases(73.796%) with resectable tumor, 177 cases(4.371%) with unresectable tumor and 884 cases(21.833%) with tumor unassessable for resectabi-lity. Of the 2 988 cases with resectable tumor, there were 2 036 cases(68.139%) undergoing radical resection, 504 cases(16.867%) undergoing non-radical resection and 448 cases(14.994%) with operation unassessable for curative effect. Of the 2 447 cases with complete pathological staging data and follow-up data who underwent surgical treatment, there were 53 cases(2.166%) with unresectable tumor, 300 cases(12.260%) with resectable tumor and receiving non-radical resection, 1 441 cases(58.888%) with resectable tumor and receiving radical resection, 653 cases(26.686%) with resectable tumor and receiving operation unassessable for curative effect. There were 733 cases not undergoing surgical treatment with complete pathological staging data and follow-up data. There was a significant difference in the overall survival between cases not undergoing surgical treatment, cases undergoing surgical treatment for unresectable tumor, cases undergoing non-radical resection for resectable tumor and cases undergoing radical resection for resectable tumor ( χ2=121.04, P<0.001). (5) Multimodality therapy and prognosis: of 6 159 patients, there were 541 cases(8.784%) under-going postoperative adjuvant chemotherapy and advanced chemotherapy, 76 cases(1.234%) under-going radiotherapy. There were 1 170 advanced gallbladder cancer (pathological staging ≥stage Ⅲa) patients undergoing radical resection, including 126 cases(10.769%) with post-operative adjuvant chemotherapy and 1 044 cases(89.231%) without postoperative adjuvant chemo-therapy. There was no significant difference in the overall survival between cases with post-operative adjuvant chemotherapy and cases without postoperative adjuvant chemotherapy ( χ2=0.23, P=0.629). There were 658 patients with pathological staging as stage Ⅲa who underwent radical resection, including 66 cases(10.030%) with postoperative adjuvant chemotherapy and 592 cases(89.970%) without postoperative adjuvant chemotherapy. There was no significant difference in the overall survival between cases with postoperative adjuvant chemotherapy and cases without postoperative adjuvant chemotherapy ( χ2=0.05, P=0.817). There were 512 patients with pathological staging ≥stage Ⅲb who underwent radical resection, including 60 cases(11.719%) with postoperative adjuvant chemotherapy and 452 cases(88.281%) without postoperative adjuvant chemotherapy. There was no significant difference in the overall survival between cases with postoperative adjuvant chemo-therapy and cases without post-operative adjuvant chemo-therapy ( χ2=1.50, P=0.220). Conclusions:There are more women than men with gallbladder cancer in China and more than half of patients are diagnosed at the age of 56 to 75 years. Cases undergoing ultrasound, CT, serum CA19-9 examination before initial diagnosis are independent influencing factors influencing initial diagnosis of gallbladder cancer patients. Preoperative resectability evaluation can improve the therapy strategy and patient prognosis. Adjuvant chemotherapy for gallbladder cancer is not standardized and in low proportion in China.

Interstitial fluid (ISF) flow through vascular adventitia has been discovered recently. However, its kinetic pattern was unclear. We used histological and topographical identification to observe ISF flow along venous vessels in rabbits. By magnetic resonance imaging (MRI) in live subjects, the inherent pathways of ISF flow from the ankle dermis through the legs, abdomen, and thorax were enhanced by paramagnetic contrast. By fluorescence stereomicroscopy and layer-by-layer dissection after the rabbits were sacrificed, the perivascular and adventitial connective tissues (PACTs) along the saphenous veins and inferior vena cava were found to be stained by sodium fluorescein from the ankle dermis, which coincided with the findings by MRI. The direction of ISF transport in a venous PACT pathway was the same as that of venous blood flow. By confocal microscopy and histological analysis, the stained PACT pathways were verified to be the fibrous connective tissues, consisting of longitudinally assembled fibers. Real-time observations by fluorescence stereomicroscopy revealed at least two types of spaces for ISF flow: one along adventitial fibers and another one between the vascular adventitia and its covering fascia. Using nanoparticles and surfactants, a PACT pathway was found to be accessible by a nanoparticle of <100 nm and contained two parts: a transport channel and an absorptive part. The calculated velocity of continuous ISF flow along fibers of the PACT pathway was 3.6‒15.6 mm/s. These data revealed that a PACT pathway was a "slit-shaped" porous biomaterial, comprising a longitudinal transport channel and an absorptive part for imbibition. The use of surfactants suggested that interfacial tension might play an essential role in layers of continuous ISF flow along vascular vessels. A hypothetical "gel pump" is proposed based on interfacial tension and interactions to regulate ISF flow. These experimental findings may inspire future studies to explore the physiological and pathophysiological functions of vascular ISF or interfacial fluid flow among interstitial connective tissues throughout the body.

Objective:To evaluate the clinical characteristics and prognosis of gallbladder cancer (GBC) patients in China.Methods:This retrospective multicenter cohort study enrolled 3 528 consecutive GBC patients diagnosed between January 2010 to December 2017 in 15 hospitals from 10 provinces. There were 1 345 (38.12%) males and 2 183 (61.88%) females.The age of diagnosis was (63.7±10.8) years old (range: 26 to 99 years old) .There were 213 patients (6.04%) in stage 0 to Ⅰ, whereas 1 059 (30.02%) in stage Ⅱ to Ⅲ, 1 874 (53.12%) in stage Ⅳ, and 382 (10.83%) unavailable. Surgery was performed on 2 255 patients (63.92%) . Three hundred and thirty-six patients received chemotherapy or radiotherapy (9.52%; of which 172 were palliative); 1 101 (31.21%) received only supportive treatment.The patient source, treatment and surgery, pathology, concomitant gallstone, and prognosis were analyzed.Results:Among the 3 528 GBC patients, 959 (27.18%) were from East China, 603 (17.09%) from East-North China, 1 533 (43.45%) from Central China, and 433(12.27%) from West China. Among the 1 578 resectable tumor, 665 (42.14%) underwent radical surgery, 913 (57.86%) underwent surgery that failed to follow the guidelines.Eight hundred and ninety-one (56.46%) patients were diagnosed before surgery, 254 (16.10%) during surgery, and 381 (24.14%) after surgery (time point of diagnosis couldn′t be determined in 52 patients) .Among the 1 578 patients with resectable tumor, 759 (48.10%) had concomitant gallstone.Among the 665 patients underwent radical surgery, 69 (10.4%) showed positive resection margin, 510 (76.7%) showed negative resection margin, and 86 (12.9%) unreported margin status.The 5-year overall survival rate (5yOS) for the 3 528-patient cohort was 23.0%.The 5yOS for patients with resectable tumor was 39.6%, for patients with stage ⅣB tumor without surgery was 5.4%, and for patients with stage ⅣB tumor underwent palliative surgery was 4.7%.Conclusions:More than half GBC patients in China are diagnosed in stage Ⅳ.Curative intent surgery is valuable in improving prognosis of resectable GBC.The treatment of GBC needs further standardization.Effective comprehensive treatment for GBC is in urgent need.

Objective:To evaluate the clinical characteristics and prognosis of gallbladder cancer (GBC) patients in China.Methods:This retrospective multicenter cohort study enrolled 3 528 consecutive GBC patients diagnosed between January 2010 to December 2017 in 15 hospitals from 10 provinces. There were 1 345 (38.12%) males and 2 183 (61.88%) females.The age of diagnosis was (63.7±10.8) years old (range: 26 to 99 years old) .There were 213 patients (6.04%) in stage 0 to Ⅰ, whereas 1 059 (30.02%) in stage Ⅱ to Ⅲ, 1 874 (53.12%) in stage Ⅳ, and 382 (10.83%) unavailable. Surgery was performed on 2 255 patients (63.92%) . Three hundred and thirty-six patients received chemotherapy or radiotherapy (9.52%; of which 172 were palliative); 1 101 (31.21%) received only supportive treatment.The patient source, treatment and surgery, pathology, concomitant gallstone, and prognosis were analyzed.Results:Among the 3 528 GBC patients, 959 (27.18%) were from East China, 603 (17.09%) from East-North China, 1 533 (43.45%) from Central China, and 433(12.27%) from West China. Among the 1 578 resectable tumor, 665 (42.14%) underwent radical surgery, 913 (57.86%) underwent surgery that failed to follow the guidelines.Eight hundred and ninety-one (56.46%) patients were diagnosed before surgery, 254 (16.10%) during surgery, and 381 (24.14%) after surgery (time point of diagnosis couldn′t be determined in 52 patients) .Among the 1 578 patients with resectable tumor, 759 (48.10%) had concomitant gallstone.Among the 665 patients underwent radical surgery, 69 (10.4%) showed positive resection margin, 510 (76.7%) showed negative resection margin, and 86 (12.9%) unreported margin status.The 5-year overall survival rate (5yOS) for the 3 528-patient cohort was 23.0%.The 5yOS for patients with resectable tumor was 39.6%, for patients with stage ⅣB tumor without surgery was 5.4%, and for patients with stage ⅣB tumor underwent palliative surgery was 4.7%.Conclusions:More than half GBC patients in China are diagnosed in stage Ⅳ.Curative intent surgery is valuable in improving prognosis of resectable GBC.The treatment of GBC needs further standardization.Effective comprehensive treatment for GBC is in urgent need.

Objective To observe the influence of Hemin on both the expression of neuroglobin (Ngb) and Tau protein phosphorylation in rats with vascular dementia (VD),and explore the effect and mechanism of Ngb in VD. Methods VD model was established in rats with a permanent bilateral common carotid arteries occlusion(2-VO). Fifty four healthy male SD rats were randomly divided into 3 groups:sham operation group,VD group and Hemin group. According to ischemic time,the animals in each group were randomly allocated into 1 week subgroup,4 weeks subgroup and 8 weeks subgroup(n=6 in each subgroup). The learning and memory ability of rats were evaluated by Morris water maze test. The brain histopathological changes were observed by HE staining and the expression of Ngb and phosphorylated Tau ( p-Tau) was de-termined by Western blot. Results Compared with the sham operation group,after 2-VO the escape latency extended (all P<0. 05) and cross-platform performance reduced in rats in both VD group and Hemin group (all P<0. 05). The learning and memory ability of rats in Hemin group was better than that in VD group at the corresponding time point:the increase in the number of crossing platforms(1 week:Hemin group (7. 00± 0. 89) times vs VD group (5. 50±1. 22) times,t=2. 42,P<0. 05;4 weeks:Hemin group (5. 33±0. 52) times vs VD group (3. 50±1. 04) times,t=3. 84,P<0. 01;8 weeks:Hemin group (6. 50±0. 55) times vs VD group (4. 50±1. 05) times,t=4. 14,P<0. 01). The expression of Ngb and phosphorylated Tau (p-Tau) increased in VD group and Hemin group (P<0. 01). Compared with VD group,the expression of Ngb in Hemin group was increased(1 week:Hemin group (3. 45±0. 23) vs VD group (2. 56±0. 08),t=5. 67,P<0. 01;4 weeks:Hemin group (3. 08±0. 13) vs VD group (2. 28±0. 08),t=7. 96,P<0. 01;8 weeks:Hemin group (2. 82± 0. 12) vs VD group (2. 05±0. 10),t=7. 28,P<0. 01),while p-Tau was decreased (1 week:Hemin group (1. 57±0. 12) vs VD group (2. 40±0. 15),t=7. 62,P<0. 01;4 weeks:Hemin group ( 2. 14±0. 21) vs VD group (3. 18±0. 14),t=8. 23,P<0. 01;8 weeks:Hemin group (1. 83±0. 13) vs VD group (2. 79±0. 19), t=4. 91,P<0. 01). In VD group and Hemin group,the learning and memory ability exhibited a negative cor-relation with Ngb (r=-0. 892,P<0. 01),whereas a positive correlation with p-Tau (r=0. 932,P<0. 01). Conclusion Hemin induces high expression of Ngb and inhibits Tau phosphorylation in VD rats. Ngb may play a neuroprotective role in the development of VD by regulating Tau phosphorylation.